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arXiv · 2506.08104

Dense Matter in Neutron Stars with eXTP

Ang Li·Anna L. Watts·Guobao Zhang·Sebastien Guillot·Yanjun Xu·Andrea Santangelo·Silvia Zane·Hua Feng·Shuang-Nan Zhang·Mingyu Ge·Liqiang Qi·Tuomo Salmi·Bas Dorsman·Zhiqiang Miao·Zhonghao Tu·Yuri Cavecchi·Xia Zhou·Xiaoping Zheng·Weihua Wang·Quan Cheng·Xuezhi Liu·Yining Wei·Wei Wang·Yujing Xu·Shanshan Weng·Weiwei Zhu·Zhaosheng Li·Lijing Shao·Youli Tuo·Akira Dohi·Ming Lyu·Peng Liu·Jianping Yuan·Mingyang Wang·Wenda Zhang·Zexi Li·Lian Tao·Liang Zhang·Hong Shen·Constança Providência·Laura Tolos·Alessandro Patruno·Li Li·Guozhu Liu·Kai Zhou·Lie-Wen Chen·Yizhong Fan·Toshitaka Kajino·Dong Lai·Xiangdong Li·Jie Meng·Xiaodong Tang·Zhigang Xiao·Shaolin Xiong·Renxin Xu·Shan-Gui Zhou·David R. Ballantyne·G. Fiorella Burgio·Jérôme Chenevez·Devarshi Choudhury·Anthea F. Fantina·Duncan K. Galloway·Francesca Gulminelli·Kai Hebeler·Mariska Hoogkamer·Jorge E. Horvath·Yves Kini·Aleksi Kurkela·Manuel Linares·Jérôme Margueron·Melissa Mendes·Micaela Oertel·Alessandro Papitto·Juri Poutanen·Nanda Rea·Achim Schwenk·Xin-Ying Song·Isak Svensson·David Tsang·Aleksi Vuorinen·Nils Andersson·M. Coleman Miller·Luciano Rezzolla·Jirina R. Stone·Anthony W. Thomas
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Abstract

In this White Paper, we present the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission to constrain the equation of state of dense matter in neutron stars, exploring regimes not directly accessible to terrestrial experiments. By observing a diverse population of neutron stars - including isolated objects, X-ray bursters, and accreting systems - eXTP's unique combination of timing, spectroscopy, and polarimetry enables high-precision measurements of compactness, spin, surface temperature, polarimetric signals, and timing irregularity. These multifaceted observations, combined with advances in theoretical modeling, pave the way toward a comprehensive description of the properties and phases of dense matter from the crust to the core of neutron stars. Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences, the eXTP mission is planned to be launched in early 2030.

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Ang Li, Anna L. Watts, Guobao Zhang, Sebastien Guillot, Yanjun Xu, Andrea Santangelo, Silvia Zane, Hua Feng, Shuang-Nan Zhang, Mingyu Ge, Liqiang Qi, Tuomo Salmi, Bas Dorsman, Zhiqiang Miao, Zhonghao Tu, Yuri Cavecchi, Xia Zhou, Xiaoping Zheng, Weihua Wang, Quan Cheng, Xuezhi Liu, Yining Wei, Wei Wang, Yujing Xu, Shanshan Weng, Weiwei Zhu, Zhaosheng Li, Lijing Shao, Youli Tuo, Akira Dohi, Ming Lyu, Peng Liu, Jianping Yuan, Mingyang Wang, Wenda Zhang, Zexi Li, Lian Tao, Liang Zhang, Hong Shen, Constança Providência, Laura Tolos, Alessandro Patruno, Li Li, Guozhu Liu, Kai Zhou, Lie-Wen Chen, Yizhong Fan, Toshitaka Kajino, Dong Lai, Xiangdong Li, Jie Meng, Xiaodong Tang, Zhigang Xiao, Shaolin Xiong, Renxin Xu, Shan-Gui Zhou, David R. Ballantyne, G. Fiorella Burgio, Jérôme Chenevez, Devarshi Choudhury, Anthea F. Fantina, Duncan K. Galloway, Francesca Gulminelli, Kai Hebeler, Mariska Hoogkamer, Jorge E. Horvath, Yves Kini, Aleksi Kurkela, Manuel Linares, Jérôme Margueron, Melissa Mendes, Micaela Oertel, Alessandro Papitto, Juri Poutanen, Nanda Rea, Achim Schwenk, Xin-Ying Song, Isak Svensson, David Tsang, Aleksi Vuorinen, Nils Andersson, M. Coleman Miller, Luciano Rezzolla, Jirina R. Stone, Anthony W. Thomas. 2025-09-08. Dense Matter in Neutron Stars with eXTP. https://doi.org/10.1007/s11433-025-2761-4

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